Utility vehicles such as heavy goods vehicles or buses, or trailers of heavy goods vehicles, generally have a box shape, which allows for effective use of available loading space and direct access to the loading space via the rear. During travel, however, the box shape leads to severe breakaway turbulence behind the rear of the vehicle and, hence, to poor aerodynamic properties. Rear spoilers serve to improve the aerodynamics of a vehicle and can reduce fuel consumption, accordingly.
For this, DE 10 2009 014 860 A1 proposes forming a rear spoiler for a utility vehicle on the sides and upper edge of the rear with several adjustable air guiding surfaces, which are substantially curved inward and adjustable separately in order to adapt automatically to the respective air flow during travel.
Some utility vehicles have attachments with an access opening at the rear, which is closed by a roller shutter. Such vehicles can generally be reversed up to a ramp without the driver first having to get out in order to open the roller shutter. With rear spoiler designs such as described in DE 10 2009 014 860 A1, reversing up to a ramp is problematic due to the air guide surfaces protruding at the rear.